The latest release of Asterisk 1.8 (including any distributions based on this such as FreePBX) out of the box will not be compatible with our trunk services (SIP and IAX).
This is because SRTP (Secure RTP) is enabled by default and is not supported on our outbound gateways.
If you are trying to setup FreePBX with our products, then you must ensure that the following changes are made to your configuration files.
In sip_custom.conf, ensure that there is a line:
...and reload asterisk to enable this setting.
Another method is to add:
noload => res_srtp.so
...into the file modules.conf to permanently disable RTP encryption.
We are also aware of an issue where PBX solutions built using Asterisk 1.8.0 to 1.8.2 will not accept incoming calls from our network. This is due to a known bug in these versions which means they are incompatible with the later version of Asterisk that Gradwell uses. Please ensure that the version of Asterisk you use is at least 1.8.3